Include path in hash of file.

[josephwarrick]

#3 This uses the path of the file in addition to the content of the file to ensure that each input file gets cached at a unique location.

[martinheidegger]

Even though #5 or #6 might be fixing the issue described in #3 I still think it might be a good idea to have caching per file-basis as an option. i.e.

console.log(__dirname)

Would need to result in a different output depending on the folder it was stored in.